A number of sweetener compositions and corresponding methods of manufacture have been disclosed in the prior art. Similarly, the prior art has disclosed various products formed from fruits and corresponding methods of manufacture. These prior art products and methods of manufacture are discussed in relative detail below in order to assure an understanding of the present invention. The following discussion deals first with various sweeteners followed by a discussion of fruit products to be distinguished from the present invention.
Significant controversy has developed over the possible deleterious effects of large amounts of sucrose, synthetic sweeteners and refined simple carbohydrates in the human diet. The United States and Europe have recommended modifications in the diet which include a decrease in the uptake of simple sugars, and an increase in complex carbohydrates.
It has also been recommended that sucrose consumption be decreased based on its cariogenic effects and on the significant concern and controversy with regard to the role of dietary sucrose in the etiology of heart disease and diabetes.
Low calorie sweeteners have been used as an alternative to sucrose; however, concern has been expressed with regard to their carcinogenic and other potentially hazardous side effects.
Refined sweeteners such as corn syrup, dextrose and fructose have also been used as an alternative to sucrose. However, they are considered "empty" carbohydrate calories because they lack naturally occurring nutritional components such as vitamins, minerals and proteins which are now believed to aid in the digestion of carbohydrates.
Sweetener compositions which are currently known and used as alternatives to sucrose may be divided into three categories. These categories are titled low calorie sweeteners, refined sweeteners and natural or nutritious sweeteners in the following discussion.
Low calorie sweeteners include those sweetening compositions described in Glicksman et al, U.S. Pat. No. 4,001,456; Grosvenor U.S. Pat. No. 3,011,897; Schmitt et al, U.S. Pat. No. 3,653,922 and Fruda et al, U.S. Pat. No. 3,971,857. These sweetening compositions have been prepared by diluting the sweetening power of synthetic sweeteners such as saccharine, cyclamate or dipeptides with dextrose, sucrose, polyglucose, corn syrup solids or maltodextrins.
In an effort to bulk or expand these products to have a volume (but not weight or density) similar to sucrose, various techniques have been employed including dry-blending followed by agglomeration, spray-drying and vacuum drum drying. These products are unique and have the distinct advantage of fewer calories than an equivalent volume of sucrose. Some of these sweeteners, which include bulking agents such as corn syrup solids or maltodextrin in the formulation, also have the advantage of having complex carbohydrates. However, the low bulk density characteristic of these reduced calorie sweeteners also represent a very limited source (less than 0.5g/teaspoon or 5 cc) of complex carbohydrates.
Very importantly, the low calorie sweeteners have the disadvantage of containing controversial synthetic sweeteners which also have off-tastes and which decompose under certain food processing conditions. They also have the disadvantage of a substantially lower bulk density than sucrose, thereby excluding their use as a direct substitute for sucrose in many dry food products. Lastly, these low calorie sweeteners are also obviously void of naturally occurring nutritional components such as protein, vitamins and minerals.
The concept of blending refined sugars to produce sweetening composition products which contain reduced amounts of sucrose or no sucrose have been described in Batterman et al, U.S. Pat. No. 4,676,991; Batterman et al, U.S. Pat. No. 4,737,368; McNamara et al, U.S. Pat. No. 3,836,396 and Walon, U.S. Pat. No. 4,049,466. In all of these products, refined fructose has been used to replace or reduce the amount of sucrose.
In the two Batterman et al references, a blend of fructose and sucrose alone was thought to be advantageous because less of the resulting sweetening composition product was required to sweeten foods. This was due to the increased sweetening capacity of fructose which is 1.7 times that of sucrose.
The McNamara et al reference revealed that a sweetening composition product composed of sucrose, fructose and maltose actually reduced cariogenicity (tooth decay) which has been associated with sucrose alone.
The Walon reference taught that a sweetener composition product can be made by spray-drying a blend of fructose syrup with 50 to 70 weight percent of maltodextrin.
All of the sweetening compositions were reported to be similar in behavior, appearance, sweetness and bulk density when compared with sucrose. The primary disadvantage of these refined sweeteners is that they contained no other nutritional components such as vitamins, minerals and proteins, and for the most part are considered "empty" carbohydrate calories. The water whiteness of the refined sweeteners as in the case of the corn syrup, or sucrose dissolved in water, is also considered a disadvantage since the consumer perceives this lack of color as evidence of the deficiency of natural nutritional components.
Also, very recently, there has been some question with regard to the toxicity of fructose because of its metabolic competition with glucose. Consequently, sweetening compositions which contain more than 25% fructose on a solids weight basis have the potential of being deleterious to the individual.
The last category of sweetening compositions which may serve as an alternative to sucrose includes the natural and nutritious sweeteners. Nutritious sweeteners are understood to contain nutritional components such as vitamins, minerals and proteins which occur naturally in addition to the obvious carbohydrate content. These nutritious sweeteners include honey, maple, molasses, cane juice and hydrolyzed whole grain (sorghum, rice and barley) products. The primary disadvantage connected with these natural sweeteners if the distinct flavor associated with them making them undesirable as a substitute for sucrose in many food applications. Another disadvantage is the higher cost of natural sweeteners relative to sucrose making them economically unfeasible for many food applications where sucrose is currently used.
The above mentioned nutritional sweeteners have been available in liquid and solid forms. The solid sweetening compositions made from honey were a combination of fructose, glucose and complex carbohydrates. The complex carbohydrates were added as a drying aid.
Dried molasses also required complex carbohydrates as a driving aid and resulted in a sweetening composition containing glucose, fructose and sucrose (greater than 25% on a dry weight basis) and complex carbohydrates. Maple syrup and cane juice have been dried directly by evaporation techniques and resulted in sweetening compositions primarily comprising sucrose (greater than 75% on a dry weight basis) and residual amounts of fructose and glucose. The hydrolyzed whole grain products have also been dried directly by drum or spray drying to result in a sweetening composition including a combination of glucose, maltose and complex carbohydrates.
All of the above mentioned nutritional sweeteners contain at least about 0.5% by weight combined protein, vitamins and minerals and are usually colored as opposed to the whiteness of refined sucrose or the water whiteness of corn syrup. This relatively small percentage of nutritional components has been considered by some to be essential in the digestion and subsequent metabolism of carbohydrates.
Lately, there has been a tremendous surge of products which incorporate fruit juice, especially in products such as soft drinks. These products have been well received by the health conscious consumers. Fruit juice concentrates and, more recently, powdered fruit juice have been used as commercial items of trade to impart desirable flavors as well as some sweetness to these products.
Fruit juice concentrates are deficient in complex carbohydrates but do have a natural balance of fructose, glucose and sucrose and nutritional components such as viatmins, minerals and proteins. The primary difference between fruit juice and fruit juice concentrate is that the latter has been depectinized so as to allow concentration to at least 40% and preferably to 60 or 72% soluble solids without gelation.
The fruit juice concentrates provide economical benefits for reducing shipping costs by not having to transport unnecessary water weight. Unfortunately, these concentrates are susceptible to microbial instability and have a very limited shelf life unless refrigerated or frozen. Consequently, it is difficult and costly for many manufacturers to use these fruit products because of the necessary refrigerated storage conditions.
Further concentration to about 78% soluble solids of the 60 to 72% fruit juice concentrates results in a significantly more stable product which does not need refrigeration. However, undesirable browning and flavor alterations have been found to result from this concentration and to preclude its use.
Use of juice concentrates with less than 72% soluble solids, in food product formulations, has been severely limited due to their functional inability to be substituted on a 1:1 basis for corn syrup of approximately 80% soluble solids (the ingredient they are most likely replacing).
The flavor associated with these fruit juice concentrates of less than 72% soluble solids has also restricted their usage as a sweetener alternative for liquid sucrose or corn syrup. So called "deflavorized", "decolorized" and even "reduced acid" juice concentrates can be made from any clear fruit juice concentrate and have been made available commercially. "Fruit syrup concentrates" (as opposed to "fruit juice concentrates") are juice concentrates (thus depectinized) which are processed through a separate ion exchange system resulting in a substantially reduced flavor, color, acid and nutrients. However, some of these concentrates, and particularly pineapple, pear and mixed fruit, still exhibited significant color and fruit flavor identification, thus limiting their application.
The flavor associated with these fruit juice concentrates or fruit syrup concentrates, their poor storage stability, their physical and functional inability to be directly substituted for corn syrup or liquid sucrose in food formulations other than liquid beverages, and their high cost relative to sucrose or corn syrup have restricted their usage as an alternative sweetener. This is exemplified by the common use of fruit juice concentrates predominantly in the beverage industry at less than 10% by weight reconstituted juice, the primary sweetness being derived from alternative sources such as corn syrup products, artificial sweeteners, or sucrose.
Powdered fruit juices have been described in the literature for the purpose of preserving the fruit juice for later reconstitution with water and more specifically preserving the flavor material as well as the nutritional components. Because of the difficulties found in drying these juices which contain fructose, glucose and sucrose, as well as vitamins, minerals and proteins, a variety of different drying aids have been used. Hunter et al, U.S. Pat. No. 4,537,637 and Gupta et al, U.S. Pat. No. 3,953,615, disclosed hydration drying of fruit juice by the use of anhydrous alpha-glucose. Kern, U.S. Pat. No. 1,204,880 taught the use of insoluble cellulose fiber to dry and preserve fruit juice. Lee, U.S. Pat. No. 2,543,142 disclosed the use of hemicellulose xylan and calcium bearing phytates to dry and preserve fruit juice.
Gupta, U.S. Pat. No. 4,112,130; Stern, U.S. Pat. No. 3,483,032 and Fleming, U.S. Pat. No. 1,361,238 taught the use of hydrolyzed starch for the preservation of fruit juices with their flavors and natural nutritional components.
The Fleming reference specifically disclosed the use of hydrolyzed starch containing glucose, maltose and approximately 50% dextrin, for the drying of the 100% pure unconcentrated fruit juice. The Stern reference taught that 100% pure unconcentrated fruit juices could be readily dried using corn syrup solids in combination with lactose. The Gupta reference taught the use of solid maltodextrin for the drying of 100% pure orange juice. It was found in these latter patents that dried hydrolyzed starch products having a dextrose equivalent (D.E.) of less than 20 (by definition, hydrolyzed starch products of less than 20 D.E. may also be termed maltodextrins) were particularly effective as a drying aid for 100% pure fruit juices. By 1970, dried maltodextrin was a commercial item of trade. Liquid maltodextrin on the other hand has not been readily available due to its instability at 70% soluble solids and its extremely high viscosity even at 70% soluble solids, making handling of this raw material very difficult. Consequently, dried maltodextrin as opposed to the syrup form has been the preferred ingredient as indicated, for example, by its usage in the Gupta and Stern references noted above. The preparation and use of maltodextrins as a drying aid have been described in Horn et al, U.S. Pat. No. 3,826,857; Harjes et al, U.S. Pat. No. 3,974,033 and the Walon reference noted above. Accordingly, those references as well as the other U.S. Patents discussed herein are incorporated by reference to the extent that they will facilitate a better understanding of the present invention.
The aforementioned powdered fruit juices are used primarily for flavoring and/or reconstitution to liquid fruit juice beverages. In all of the above cases, the object of drying the fruit juice necessitated the preservation of the flavor material as well as the nutritional components.
Denny, U.S. Pat. No. 1,746,994 and Bartz, U.S. Pat. No. 2,525,761 taught the deflavorization of raisin syrup and fruit juice, respectively.
In the Denny reference, a syrup was made from raisins (as opposed to the whole fruit) and deflavorized by physical concentration of the extracted raisin liquor to 60.degree. Brix and removal of crystallized tartrate compounds followed by treatment with lime which reportedly removed the residual tartrate compounds along with tannins and some color and flavor materials. Carbon was used to complete the removal of any residual color in the syrup.
The Bartz reference taught that fruit juices could be deflavorized, thereby producing mono- and di-saccharides sugars, liquid sugar and edible syrups. Unfortunately, the process claimed involved depectinization followed by chemical deflavorization via the addition of basic salts (aluminum, barium, strontium and preferably lead were given as examples). This was followed by the subsequent removal of divalent metallic elements as insoluble oxalates. Carbon was used primarily and essentially to remove all the color material to produce a water white liquor as well as removing "any remaining bitter principles and lead salts", thus indicating the use of carbon primarily for decolorization and secondarily for deflavorization purposes. It is understood that residual concentrations of the basic salts in parts per million (ppm) would exist in the finished product so that these basic salts would be contaminants additionally distinguishing the product.
It was also claimed that the water white liquor product of this invention could be spray dried directly (without the use of drying aids) to produce a product in solid form.
A variety of drying techniques have been used in making powdered fruit juices. These include spray drying at relatively low temperatures to preserve flavor and nutritional components, vacuum drum drying, rotary vacuum drying, and a relatively new method involving extrusion drying into a relatively cool solvent such as isopropyl alcohol.
Thus, although a wide variety of sweeteners have been made available in the prior art, there has been found to remain a need for a sweetener composition or compositions having improved, enhanced and novel characteristics as defined in greater detail below.